The present invention relates to a tamper evident seal and system for containers whereby a consumer may be assured that the seal on a product has not been tampered with prior to purchase. The invention is particularly directed to an improved combination of a tamper evident seal and indicia for use on bottles and similar product packaging.
Heat shrink seals are in common use on a variety of products in the market place as a means to reduce or prevent tampering with such products. The application of a seal occurs at the time of packaging the product after a closure has been applied to the product container and the seal generally remains intact until the ultimate purchaser removes it. In this manner the purchaser is generally assured that the product within the package is in the same condition as when it was initially packaged and has not been tampered with at any point between its manufacture and purchase.
Prior seal means have generally been limited to heat shrink collars placed over the cap and neck of a bottle and shrunk into place. Occasionally, a secondary seal or label, generally in the nature of a tax stamp, is first applied and the collar then shrunk thereover. These types of seal means are represented by U.S. Pat. No. 2,447,983 to Little, U.S. Pat. No. 2,790,286 to Snyder and U.S. Pat. No. 3,095,103 to Harrison. The Little patent discloses a heat shrinkable sleeve having an opaque portion and a transparent portion which is designed to be used in combination with a tax stamp placed over the package closure. The sleeve is oriented so that the tax stamp shows through the transparent portion. Snyder discloses a secondary closure in the nature of a shrink wrap sleeve which is dipped in a swelling agent to render the sleeve tacky so that it will adhere to the container when shrunk. As an alternative, Snyder also discloses that a heat activatable adhesive may be coated on the inner surface of the sleeve instead of using the swelling agent. Although the present invention may also employ a heat activatable adhesive, there are other aspects which are neither disclosed nor suggested by the Snyder patent and which will become clear in the subsequent discussion. The Harrison patent discloses a heat shrink closure or seal which is applied in combination with a tear strip, the shrinking of the seal material serving to hold the tear strip in place. However, the tear strip is not itself adhered to the container.
Such prior art seals have a significant drawback in that there is no provision for a means to directly inform the purchaser that there should have been a seal on the container wherein that information is in direct proximity to the seal and is not revealed until the seal is removed and which is itself not readily removable. Other methods of providing such information have generally been limited to fine print on product labels which are more often overlooked than looked at. In contrast, the present invention provides a combination of seal means and indicia which may be used on any closure/container combination and which provides a direct cooperative relationship between the seal means and indicia which are directly applied to a container and/or closure to thereby alert the consumer that the seal has been removed or compromised. An alternative embodiment provides a combination of seal and indicia which is even more readily evident of an attempted seal removal when the seal has not been completely removed and which is positioned on a container in a manner such that it is not visible until a container closure has been removed.
Still other seals and methods employ complex color change compositions or two part tape means whereby removal, or attempted removal results in the exposure of a color change composition or indicia which is part of the seal means such that warning of the prior opening is given to the purchaser by a color change or the exposure of indicia which is an integral part of the tape and which is ultimately removable from the container. These types of seals are represented in the prior art by U.S. Pat. No. 4,511,052 to Klein, et al., which discloses a color change means, and U.S. Pat. No. 4,652,473 to Han, which discloses a two part tape having an exposable color or indicia bearing portion adjacent an adhesive and which is thin and deformable when removal is attempted. However, in Han the indicia is part of the sealing tape and there is nothing to restrict its complete removal with the effect that the consumer has no direct warning that a seal should have been present but has been removed. Similarly, the color change tape of Klein, et al., may also be completely removed leaving no indication to the consumer that a safety seal was present but has been removed.